Jetevator system design



Sept. 3, 1963 F. R. BARNET 3,102,390

JETEVATOR SYSTEM DESIGN Fil ed March 9, 1960 FIGJT INVENTOR.

9 8 I FREDRICK RBARNET ATTYS;

United States Patent ta of the Navy ry Filed Mar. 9, 1960, Ser. No.13,967

3 Claims. (Cl. 60-3555) (Granted under Title 35, US. Code (1952), sec.266) The invention described herein may be manufactured and used by orfor the Government of the United States of America for governmentalpurposes without the payment of any royalties thereon or therefor.

This invention relates to a sealing ring for application between anexhaust nozzle and a jetevator.

Vector control on missiles may be obtained by the deflection of theexhaust gases at the nozzle termination by a jetevator which is afiixedto the nozzle. The present high energy propellants contain largequantities of aluminum. This is present in the exhaust gases either asvapor or a highly dispersed liquid, and many times is deposited on theinner surface of the jetevator so as to interfere with its operation.This depositing occurs because the jetevator acts as a heat sink and thealumina is condensed and adheres to the inner surface of the jetevator.This adherence is sometimes sufficient to interfere with the operationand render the jetevator inoperative.

It is an object of the present invention to provide a seal attached tothe nozzle and in contact with the jetevator to prevent the depositionof alumina in sufiicient amounts so as to interfere with the operation.

It is another object to provide a graphite ring seal at the end of thenozzle and in contact with the inner surface of the jetevator to wipethe inner surface of the jetevator and coat said surface with a film ofgraphite to prevent the adherence of the particles of alumina in theexhaust gases to the inner surfacebof the jetevator.

It is a further object of the invention to provide a graphite annularseal at the exhaust end of the nozzle and to secure the seal to thenozzle by an adhesive and by mechanical means.

It is a still further object of the invention to provide a seal betweenthe nozzle and the jetevator which would lubricate the inner surface .ofthe jetevator during its operation and in case of alumina deposits onthe inner surface of the jetevator the graphite seal would not provide astop to prevent the operation of the jetevator but would receive thealumina particles into its comparative softer surface.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawing wherein:

FIG. 1 is a longitudinal section of a nozzle with attached seal andjetevator;

FIG. 2 is a similar view with the jetevator in a different position; and

FIG. 3 is a similar view showing how the alumina particles score thegraphite seal to permit lubrication.

Referring to the drawing wherein like numerals designate like parts inthe several figures, a nozzle 11 for a missile is illustrated having abore 12 restricted at 13 and gradually enlarged to the exhaust end 14.The nozzle has its exterior surface spherical shaped at 16 to receivethe jetevator 1-7. A pair of pins (not shown) extend from diametricalopposite points of the spherical portion and support the jetevator forlimited oscillatory movement controlled by levers or gears (also notshown).

The jetevator at its outer opening is recessed at 18.

3,102,390 Patented Sept. 3, 1963 ice Ordinarily the outer portion isspaced from the nozzle by approximately 4; inch and the alumina depositssome: times fill this space.

The exhaust end of the nozzle is recessed at 21 to receive the annularbase 22 of a graphitesealing ring 23. The sealing ring is secured to thenozzle by adhesive between the metal surface of the nozzle and thegraphite surface of the ring. Screws 24 threaded into holes 25 also holdthe ring in position. The sealing ring extends into the recess 18 and isin sealing contact with the jetevator. The inner surface of the sealingring is an extension of the inner surface of the nozzle and presents noobstruction to the flow of exhaust gases. The graphite ring serves as aseal, a bearing and a lubricant for the jetevator. It extends beyond thenozzle and into close contact with the jetevator thus preventingturbulence of exhaust gases formerly caused by the clearance between thenozzle and the jetevator.

FIG. 2 illustrates the position of the jetevator when it is used tochange the direction of flight of the missile, the exhaust gases beingdeflected by the inner surface 27 of the jetevator. The movement of thejetevator in moving from the position shown in FIG. 1 to that shown inFIG. 2 causes the inner surface 27 of the jetevator to wipe the graphitesurface of the seal resulting in a deposit of graphite on the inner face27. This deposit of graphite will inhibit the deposition of alumina onthe inner surface 27 and the closely spaced relationship of thejetevator and the graphite seal insures against the accumulation ofalumina particles between the nozzle and the jetevator.

Should the coating of graphite on the inner surface 27 be not completeand some particles of alumina are de posited, the soft surface of thegraphite seal will be scored, as seen in FIG. 3 to permit the jetevatorto function.

The close adherence of the seal to the jetevator also keeps the exhaustgases out of contact with the inner surface of the jetevator where theywere formerly directed by the inner surface 27 by reason of theclearance between the jetevator and the nozzle and prevents theoverheating of the jetevator in those bearing surfaces 28 which contactthe spherical surface 16 of the nozzle. This assists in maintaining thejetevator in operative condition as uneven expansion of these bearingsurfaces can cause binding.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood, that within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

What is claimed and desired to be secured by Letters Patent of theUnited States is:

1. An exhaust nozzle for a missile comprising a body portion having atapered bore terminating in a nozzle opening, an exterior sphericalbearing surface formed at the end of the body portion, a jetevatormounted on said bearing surface for limited movement, means for movingsaid jetevator relative to the body portion, a graphite seal mounted onthe body portion and forming the nozzle opening, said seal being incontact with the inner surface of the jetevator whereby movement of thejetevator to operative position coats the inner face of the jetevator,which after movement is exposed to the exhaust gases with a coating ofgraphite.

2. An exhaust nozzle for a missile comprising a body portion having atapered bore terminating in a nozzle opening, said body portion havingan exterior spherical surface adjacent said opening, an annular graphiteseal secured to the end :of the body portion, the inner surface of saidseal conforming to and forming part of the tapered bore, the outersurface of said seal being concentric with References Cited in the fileof this patent the spherical surface of said body portion, a jetevatorUNITED STATES PATENTS mounted for universal movement on the sphericalsurfaces of said body portion and said seal, movement of said 1 5 et a13 i i 'd herical surfaces coating a portion of 5 ea n leteYawr on Sal SP2,606,060 Brown July 15, 195.2 the mner surface of said etevator withgraphite. 2,755,620 Giuot July 24 1956 3. A nozzle according to claim 2wherein the spherical 2,779,157 I Palmer Jam 1957 surface of thegraphite seal is of greater diameter than 2,780,059 Fiedler 5 1957 thespherical surface of the body portion, to shield the bearing surface ofthe body portion from the exhaust 10 FOREIGN PATENTS gases. 567,048Canada Dec. 9, 1958

1. AN EXHAUST NOZZLE FOR A MISSILE COMPRISING A BODY PORTION HAVING ATAPERED BORE TERMINATING IN A NOZZLE OPENING, AN EXTERIOR SPHERICALBEARING SURFACE FORMED AT THE END OF THE BODY PORTION, A JETEVATORMOUNTED ON SAID BEARING SURFACE FOR LIMITED MOVEMENT, MEANS FOR MOVINGSAID JETEVATOR RELATIVE TO THE BODY PORTION, A GRAPHITE SEAL MOUNTED ONTHE BODY PORTION AND FORMING THE NOZZLE OPENING, SAID SEAL BEING INCONTACT WITH THE INNER SURFACE OF THE JETEVATOR WHEREBY MOVEMENT OF THEJETEVATOR TO OPERATIVE POSITION COATS THE INNER FACE OF THE JETEVATOR,WHICH AFTER MOVEMENT IS EXPOSED TO THE EXHAUST GASES WITH A COATING OFGRAPHITE.